Many devices for holding a poisonous bait to control crawling insects are known, ranging from simple cardboard tubes open at both ends with the bait glued inside, to more elaborate structures that have a centrally enclosed bait accessible by peripheral openings.
Such devices usually hold a dry bait and toxicant preparation.
Older examples are U.S. Pat. No. 1,372,780, which discloses a bell shaped top having side apertures, which fits over and clamps to a dish shaped base, and U.S. Pat. No. 2,123,995, which discloses a flat piece of sheet metal which is bent over an insecticidal substance to partially cover the substance while allowing insects direct access.
U.S. Pat. No. 4,563,836 to Woodruff et al. discloses an insect feeding station comprised of a simple cover which fits over a base, the base having external wall segments with entrance gaps between them and interior walls placed opposite the gaps and surrounding a central bait area. The outer walls of the present invention are formed by the cover; then entrance apertures are oriented at an angle to the required line of approach to the bait, and a ramped structure surrounds the bait well.
U.S. Pat. No. 4,837,969 to Demarest discloses a bait station having an apertured multi-lobed cover which fits over a base which has a central bait well formed by a ramped structure and inner walls which intersect the ramped structure and serve to guide insects toward the bait well.
U K. Pat. No. GB 2 128 463 A discloses an insect feeding station having an aperture-containing cover placed over a base, the base having baffle means for directing an insect toward the central bait section.
Australian Patent AU-B-73766/87 discloses the known fact that roaches are attracted to water, and claims a method of attracting roaches by including water in a poison bait composition, and suggests that the composition may be contained in a cup-like container or an absorbent medium attached to a feeding station. This patent further states that suitable bait stations are disclosed in U.S. Pat. No. 4,563,836, which discloses a feeding station designed to enclose a bait tablet or other non-liquid bait composition.
Such bait stations provide two of the three things preferred by roaches: darkness and harborage. However, there is a third preference roaches have that is not provided by such bait stations: moisture.